1NHA

Solution Structure of the Carboxyl-Terminal Domain of RAP74 and NMR Characterization of the FCP-Binding Sites of RAP74 and CTD of RAP74, the subunit of Human TFIIF

Summary for 1NHA

• Entry DOI: 10.2210/pdb1nha/pdb
• Descriptor: Transcription initiation factor IIF, alpha subunit (1 entity in total)
• Functional Keywords: transcription factor, human general transcription factor tfiif, rap74, transcription
• Biological source: Homo sapiens (human)
• Cellular location: Nucleus: P35269
• Total number of polymer chains: 1
• Total formula weight: 9344.81

Authors

Nguyen, B.D.,Chen, H.T.,Kobor, M.S.,Greenblatt, J.,Legault, P.,Omichinski, J.G. (deposition date: 2002-12-19, release date: 2003-02-25, Last modification date: 2024-05-22)

Primary citation

Nguyen, B.D.,Chen, H.T.,Kobor, M.S.,Greenblatt, J.,Legault, P.,Omichinski, J.G.
Solution Structure of the Carboxyl-Terminal Domain of RAP74 and NMR Characterization of the FCP1-Binding Sites of RAP74 and Human TFIIB.
Biochemistry, 42:1460-1469, 2003

PubMed Abstract: FCP1 (TFIIF-associated CTD phosphatase) is the only known phosphatase specific for the phosphorylated CTD of RNAP II. The phosphatase activity of FCP1 is strongly enhanced by the carboxyl-terminal domain of RAP74 (cterRAP74, residues 436-517), and this stimulatory effect of TFIIF can be blocked by TFIIB. It has been shown that cterRAP74 and the core domain of hTFIIB (TFIIBc, residues 112-316) directly interact with the carboxyl-terminal domain of hFCP1 (cterFCP, residues 879-961), and these interactions may be responsible for the regulatory activities of TFIIF and TFIIB on FCP1. We have determined the NMR solution structure of human cterRAP74, and we have used NMR methods to map the cterFCP-binding sites for both cterRAP74 and human TFIIB. We show that cterFCP binds to a groove of cterRAP74 between alpha-helices H2 and H3, without affecting the secondary structure of cterRAP74. We also show that cterFCP binds to a groove of TFIIBc between alpha-helices D1 and E1 in the first cyclin repeat. We find that the cterFCP-binding site of TFIIBc is very similar to the binding site for the HSV transcriptional activator protein VP16 on the first cyclin repeat of TFIIBc. The cterFCP-binding sites of both RAP74 and TFIIBc form shallow grooves on the protein surface, and they are both rich in hydrophobic and positively charged amino acid residues. These results provide new information about the recognition of acidic-rich activation domains involved in transcriptional regulation, and provide insights into how TFIIF and TFIIB regulate the FCP1 phosphatase activity in vivo.

PubMed: 12578358
DOI: 10.1021/bi0265473

Experimental method

SOLUTION NMR